(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The person wants to cause the 200N crate to start sliding toward the right. To achieve this, the horizontal component of the force exerted on the crate by the rope must equal 0.35 times the normal force exerted on the crate by the floor.

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[........[ +

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The box is the crate and the pluses represent the rope the guy is pulling. It makes an angle of 20 degrees with the horizontal.

2. Relevant equations

F_{f}=[tex]\mu[/tex]F_{N}

3. The attempt at a solution

So I figured that 0.35 is the [tex]\mu[/tex] for friction. Since its a leveled surface, F_{N}will equal F_{g}and thus they cancel out. The horizontal component of the F_{app}has to equal F_{f}because he's trying to move it, not accelerate it.

From this, I got F_{app}to equal 70N. The angle is 20 degrees, so the F_{app}is 74.5N (got by: 70N/cos(20)). But the back of the book is telling me it should be 66N. I don't know how I'd get that. But then again, its Engineering Statics, so maybe there is some trick? Please help?

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# Homework Help: 2D Forces

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